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Abstract

The invention provides a snapshot implementing method capable of reducing system resource expenses. On the one hand, disk resources occupied by snapshots can be reduced effectively so that utilizing rate of storage devices can be increased, and on the other hand, data movement is not needed during setting up of snapshots so that storage performance is improved. The method includes steps: firstly, snapshots of application data are set up for backup, setting up a reserved area is not needed, and only pointers need to be set up; and secondly, when application data blocks change, data movement is not needed, the modified data blocks are directly written into an available space of a snapshot and new pointers are set up. The snapshot implementing method has the advantages that firstly, absolutely low system capacity resource expenses guarantee more effective disk spaces; secondly, data movement is not needed in the whole process, so that read-write of the data blocks is omitted, disk performance is guaranteed, and more snapshots can be set up by the system; and thirdly, on one hand, disk resources occupied by snapshots can be reduced effectively so that utilizing rate of storage devices can be increased, on the other hand, data movement is not needed during setting up of the snapshots so that storage performance is improved.

Description

Translated from Chinese

一种减少系统资源开销的快照实现方法 A method of reducing system resource overhead snapshot implementation

技术领域 FIELD

[0001] 本发明涉及一种数据存储及数据保护领域，具体涉及一种快照实现方法，可以有效减少系统资源开销。 [0001] The present invention relates to a data storage and data protection, in particular to a snapshot implemented method can effectively reduce the system resource overhead.

背景技术 Background technique

[0002] Snapshot，也就是快照技术，通过指向保存在存储设备中的数据的引用标记或指针，也就是数据在某一时刻的状况，来对数据进行备份保护。 [0002] Snapshot, i.e. snapshots, by reference mark or pointer pointing to the data stored in the storage device, i.e. status data in a certain time, to protect the backup data.其工作原理核心就是建立一个指针列表，指示读取数据的地址，提供一个瞬时数据的影像，当数据有改变时，再进行复制。 Its working principle is to establish a core list of pointers, indicating the address of the read data, providing a momentary image data, when the data has changed, and then copy it.由于每次快照只是针对于差异数据进行备份，可以有效提高备份的效率，并且可以对任意时间点的数据进行恢复。 Because each snapshot is only for the differences in data backup, can improve the efficiency of backup and can recover the data at any point of time.

[0003] 但是，当前快照的实现方法存在以下两个问题：1)快照大量占用磁盘空间，降低存储设备的利用率；2)过多的数据移动，降低了磁盘的性能。 The presence of [0003] However, implementation of the current snapshot following two questions: 1) a large amount of disk space occupied snapshot, reducing the utilization of the storage device; 2) data movement too, degrades the performance of the disk.

[0004] 先来看一下现有技术快照的实现方法： [0004] first look at the implementation of the prior art snapshots:

1)对应用数据创建快照1进行备份，同时会创建快照1的预留区，快照1的指针指向已有数据块及预留区，如图1所示； 1) create a snapshot of the application data for a backup, create a snapshot of a reserved area, a snapshot pointer pointing to the existing data block and the reserve area, shown in Figure 1;

2)当应用的数据块发生变化是，根据快照1的指针的指示，要先读出快照1中与变化数据对应的旧数据，将其拷贝至快照1预留区中，并修改快照1的指针指向预留区，如图2所示。 2) When the application data block is changed, according to the pointer that indicates a snapshot of a snapshot of a first read out data corresponding to the change of the old data, the snapshot copy it to a reserved area, and modify the snapshot 1 pointer to the reserved area, as shown in FIG..然后将新数据写入磁盘，此时形成快照2，同样的，创建快照2的同时还要创建快照预留区2及指针2，如图3所示。 Meanwhile then new data is written to disk, the snapshot 2 at this time is formed, the same, create a snapshot of the snapshot 2 also create a reserved area 2 and pointer 2, as shown in FIG.应用数据块的一次变化将触发快照区内一读（旧数据)、一写(旧数据至预留区)、一写(新数据到磁盘)。 A change in the application data block area will trigger a snapshot reading (old data), a write (old data to the reserved area), a write (new data to disk).

[0005] 继续修改应用数据，同样的要先读出快照区的旧数据，将其拷贝至所有快照预留区中，改变所有旧快照指针指向预留区，如图4。 [0005] continue to modify application data, the same data is first read out the old snapshot area, copy it to reserved regions in all the snapshots, the snapshot pointer to change all the old reserved area, as shown in FIG 4.将新数据写入磁盘，形成快照3，同时创建预留区3和指针3。 The new data is written to disk, to form a snapshot 3, while creating a reserved area pointer 3 and 3.本次写操作一读三写。 The first reading of three write write.

发明内容 SUMMARY

[0006] 本发明的目的是提供一种减少系统资源开销的快照实现方法。 [0006] The object of the present invention is to provide a system to reduce the resource overhead snapshot implementation.

[0007] 本发明的目的是按以下方式实现的，本发明的快照实现方法，一方面可以有效减少快照对磁盘资源的占用，提高存储设备的利用率，另一方面，在创建快照的过程中，无需数据的移动，提高了存储性能。 [0007] The object of the present invention are achieved in the following manner, the method of the present invention to achieve the snapshot, the snapshot one can effectively reduce resource occupation of the disk, to improve the utilization of storage devices, on the other hand, during the creation of snapshots , no need to move data and improve storage performance.

[0008] 实现步骤如下： [0008] The steps are as follows:

1)对应用数据创建快照进行备份，无需创建预留区，仅创建指针； 1) Create a snapshot backup of application data, no need to create a reserved area, create only a pointer;

2)当应用数据块发生变化时，无需移动数据，直接将修改的数据块写入快照区的可用空间并创建新指针。 2) When the application data block is changed, without moving data directly write the modified data block is available space and create a new snapshot of the pointer region.

[0009] 本发明的有益效果是：新的快照实现方法与之前的方法相比具有如下优点： [0009] Advantageous effects of the present invention is: new snapshot implemented method compared to the previous method has the following advantages:

2)整个过程无需移动数据，消除了读写数据块的过程，从而保证了磁盘性能，系统可以创建更多的快照； 2) The whole process without moving the data, eliminating the process of reading and writing the data block, thereby ensuring the performance of the disk, the system can create more snapshots;

3) —方面可以有效减少快照对磁盘资源的占用，提高存储设备的利用率，另一方面，在创建快照的过程中，无需数据的移动，提高了存储性能。 3) - aspects can effectively reduce the usage of the snapshot disk resources, improve the utilization of storage devices, on the other hand, in the process of creating snapshots, no need to move data and improve storage performance.

附图说明 BRIEF DESCRIPTION

[0010] 图1 -4是传统快照的实现方法示意图； 图5-7是本发明快照的实现方法示意图。 [0010] FIG. 1-4 is a schematic diagram of a conventional implementation of a snapshot; FIG. 5-7 is a schematic view of the present invention to achieve a method snapshots.

具体实施方式 Detailed ways

[0011 ] 参照说明书附图对本发明的方法作以下详细地说明。 [0011] Referring to the method of the present invention will be described below in detail with accompanying drawings.

[0012] 本发明的快照实现方法：步骤如下： [0012] The method of the present invention is implemented snapshot: the following steps:

2)当应用数据块发生变化时，无需移动数据，直接将修改的数据块写入快照区的可用空间并创建新指针，如图6、图7所示。 2) When the application data block is changed, without moving data directly write the modified data block area of ​​a snapshot of the available space and create a new pointer, 6, 7 shown in FIG.

[0013] 除说明书所述的技术特征外，均为本专业技术人员的已知技术。 [0013] In addition to the technical features described in the specification, it is known to those skilled in the art.

Claims (1)

Translated from Chinese

1. 一种减少系统资源开销的快照实现方法，其特征在于实现步骤如下：1)对应用数据创建快照进行备份，无需创建预留区，仅创建指针；2)当应用数据块发生变化时，无需移动数据，直接将修改的数据块写入快照区的可用空间并创建新指针。 Snapshot 1. A method of reducing resource overhead system implemented method wherein steps are as follows: 1) create a snapshot backup of application data, without creating a reserved area, creating only a pointer; 2) when the application changes the data block, without moving data directly write the modified data block area of ​​a snapshot of the available space and create a new pointer.